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The Effectiveness of Intervention on Insulin Injection in Insulin-naive Patients

With Type 2 Diabetes: Application of the Transtheoretical Model

October 18, 2017

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The Effectiveness of Intervention on Insulin Injection in Insulin-naive Patients

With Type 2 Diabetes: Application of the Transtheoretical Model

Introduction

If not well controlled, diabetes can easily trigger various complications.

Maintaining a glycosylated hemoglobin (HbA1c) level lower than 7% has been

established as the standard for diabetes control. Insulin treatment has been regarded as

an effective method, and treating diabetes with insulin early on is widely considered

as an important principle for treating patients with type 2 diabetes mellitus (T2DM) in

the US and Europe. However, many studies have shown that patients with T2DM are

often reluctant to change from oral medication to insulin treatment. Research has also

found that patients with T2DM whose glycemic control was poor delayed insulin

treatment by 7 to 8 years. Therefore, it is necessary for healthcare professionals to

establish a comprehensive intervention plan to help patients with poor glycemic

control to initiate insulin injection early and adhere to the treatment. However, as far

as is known, little research has been done on this topic in Taiwan.

According to the Transtheoretical Model (TTM) proposed by Prochaska and

Diclemente, people will experience different stages of change before the actual

behavioral change takes place. Ineffectiveness of intervention to instigate

behavioral change is largely due to failure to take into account the stage of

change in which individuals are. The TTM suggests that decisional balance,

which reflects the relative difference between pros and cons, is important for

influencing the stage of change. In order to achieve behavioral change, the

perceived pros of changing must be strengthened to outweigh the cons. In

addition, individual must be self-convinced that the behavioral change is

important for themselves. Subsequently, the process for behavioral change can be

provided to facilitate behavioral change in individuals. The theory of TTM has

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been applied to change various problematic behaviors, but so far, it has yet been

used to improve the behavior of insulin initiation in insulin-naïve patients with

T2DM. Thus, this study aims to assess the effectiveness of an intervention for

insulin injection initiation based on the TTM in insulin-naïve patients with

T2DM.

Methods

Study design

The present study adopts quasi-experimental design. To avoid

contamination between participants in two study arms, cluster sampling is used.

Patients with T2DM of an endocrinology clinic in southern Taiwan are assigned

to the intervention arm, whereas patients at another endocrinology clinic in

southern Taiwan are placed in the control arm. Eligible patients that match the

inclusion criteria are recommended by doctors to initiate insulin treatment after

getting the consent forms from eligible participants. Research assistants will

subsequently collect baseline data from eligible participants. Afterwards, the

participants in the intervention arm will receive the intervention. For the control

arm, the participants will receive regular patient education originally

administered at the hospital. Data for the participants in both study arms will be

collected by research assistants at baseline, 3 months, 6 months, and 12 months

post-intervention. The main outcome variable is change in HbA1c levels, while

the change in stage of change, in insulin injection adherence, in appraisal of

insulin injection, in patient empowerment, in self-efficacy for insulin injection, in

diabetes distress, in quality of life, in triglyceride(TG), in total cholesterol (TC),

in high-density lipoprotein cholesterol(HDL-C), in low density lipoprotein

cholesterol(LDL-C), in urine albumin creatinine ratio (UACR), in estimated

glomerular filtration rate(GFR) are secondary outcome variables. The outcome

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variables and collection time points are summarized in Table 1.

Samples

The inclusion criteria of eligible participants are: (1) diagnosed with T2DM

for at least half a year; (2) aged 20-70 years old; (3) controlling diabetes only

through oral medication, without previous experience in insulin injection; (4)

HbA1c≧8.5% as measured more than twice in the most recent year. Exclusion

criteria were: (1) unable to communicate with language; (2) incapable of

self-administering insulin injection due to visual or muscular impairment.

Eligible participants who have been assessed and considered suitable for

changing to insulin treatment by doctor will be included in this study.

Sample size estimation was done according to previous literature. An

estimation of 63 participants in each study arm was calculated through setting a

middle effect size of 0.5 between the two study arms in HbA1c levels, α of 0.05,

and power of 0.8. Furthermore, an attrition rate of 20% was expected. Therefore,

each study arm should include at least 76 participants.

Measurements

Biomedical indicator measurement

The HbA1c levels, triglyceride(TG), total cholesterol (TC), high-density

lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol(LDL-C),

urine albumin creatinine ratio (UACR) will be collected through blood test.

Estimated glomerular filtration rate(GFR) will be collected through urine test.

Height and weight will be collected through body weight and height scales, and

will be converted to body mass index (weight (kg)/ height(m) 2.

Self-reported questionnaire

The other outcome variables will be collected by self-report questionnaire.

The questionnaire will include following contents.

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Demographic data & disease characteristics

Age, sex, educational level, duration of diabetes, duration of taking oral drug

before insulin therapy will be collected at baseline. Insulin treatment regimen

including type of insulin, dose, frequency of injection and blood sugar self-monitoring

will be collected after participants receiving insulin injection.

Stage of change for insulin injection. A question of stages of change for insulin

injection was developed. At baseline, the question was “If the doctor recommends that

you initiate insulin treatment right now, what would be your opinion?” Three

responses to this question included “never considered”, “under consideration and

might start within the next 6 months”, and “likely to start immediately”, which

respectively represented three early stages of change — precontemplation,

contemplation, and preparation. At the 3, 6, and 12 months post-intervention, the

question was “what’s the status of your insulin injection?” The responses were

“taking insulin injection previously, but now is stop insulin injection and never

consider to receive insulin injection again, “taking insulin injection previously, but

now is stop insulin injection, consider to start insulin injection again within next 6

months”, “still receive insulin injection but sometimes forget to inject” ,

“Continuously inject insulin but less than 6 months”, “Continuously injected insulin

and more than 6 months”.

Insulin injection adherence. An 8-item Morisky Medication Adherence Scale was

used to assess insulin injection adherence behaviors of participants. The total scores

ranged from 7 to 11. The higher scores indicate, the better insulin injection adherence

behaviors

Appraisal of insulin injection. A 13-item Decisional Balance for Inulin Injection scale

was used in the study to assess the appraisal of insulin injection. The scale comprised

subscales of positive and negative appraisal. Each item was rated from 1 (strongly

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disagree) to 5 (strongly agree). Decisional balance for insulin injection was calculated

by deducting the mean score of positive appraisal with that of negative appraisal. The

higher score indicated the higher decisional balance for insulin injection.

Empowerment perception. A 13-item Chinese version of the Diabetes Empowerment

Process Scale was used to assess the perceived level of empowerment by healthcare

providers in participants. Each item was rated on a 5-point scale with scores ranging

from 0 (strongly disagree) to 4 (strongly agree). The total score range from 13 to 65. A

higher score indicated higher perceived patient empowerment.

Self-efficacy for insulin injection. A 4-item scale was used to assess self-efficacy for

insulin injection in participants. Each item was rated on a scale from 0 to 4 with 0

indicating “no confidence”, 1 indicating “20-30% confidence”, 2 indicating “40-50%

confidence”, 3 indicating “60-70% confidence”, 4 indicating “over 80% confidence”.

A higher score represented higher confidence in performing insulin injection.

Diabetes distress. An 8-item Chinese version of the short-form Problem Areas in

Diabetes Scale was used to assess the levels of diabetes distress in participants. The

response of each item was rated from 0 (not a problem) to 4 (serious problem). The

total score ranged from 8 to 32. A higher score represented severer diabetes distress.

Quality of life. A 15-item Diabetes-Specific Quality-of-Life Scale was used to assess

the subjective appraisal of participants in their perceived degree to which their current

health-related aspects in life were affected by emotional suffering, social functioning,

adherence to treatment regimen, and diabetic-specific symptoms. Each item was rated

from “very much” (0 point) to “not at all” (4 points). The total score ranged from 0 to

60. A higher score indicated better quality of life.

Intervention plan of the intervention arm

The intervention plan contains three parts: (1) individual intervention; (2) insulin

injection follow-up management; (3) motivational group activities. Different

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intervention strategies are applied to patients according to their stages of change. In

addition, a computerized information system will be applied to facilitate data

management and recording by interveners. The strategies for individual intervention

designed according to the stage of change and the corresponding process of change

are shown in Table 2. Details of insulin injection follow-up management from

preparation stage to maintenance stage are shown in Table 3. The motivational group

activities from precontemplation stage to maintenance stage are shown in Table 4.

Usual care of the control arm

Participants in the control arm attend regular patient education at the hospital.

The contents of the education plan are as follows:

1. Teach participants the method of injection following the standard procedure,

including gathering insulin supplies, the steps of injection, and so on.

2. Hand out a step-by-step pictorial guide to participants after teaching them the

techniques and supply preparation for using insulin pen. Fill in the type and dose of

insulin and the site and time of injection on a sheet for participants and their family to

refer to after they return home.

3. Recommend patients to administer blood-glucose self-monitoring and record the

results.

4. Conduct a telephone follow-up 3 days after patient education to check on the

condition of insulin injection. Schedule a return visit after a week, during which the

doctor adjusts the medication according to the results of SMBG and instructs the rule

for dose adjustment at home.

5. Provide a hotline for patients to seek consultation when they encounter difficulties

or problems.

6. Play patient education video clips on insulin injection in the waiting room when

patients come for return visits.

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7. Provide patient education in small groups occasionally, in which insulin-treated

patients are invited to share their experience and clarify questions.

Ethical consideration

The study is approved by the Human Experiment and Ethics Committee of two

hospitals (NO. KMUHI-E(I)-20150262, TSGHIRB-1-105-05-163). Participants are

informed of their rights to refuse participation in the study without any penalty. Only

after the participants have signed the consent forms will data be collected from

participants.

Data Analysis

The statistical software program SPSS 17.0 was used for data analysis. The

Chi-squared test and independent t-test were used to compare differences in personal

characteristics and outcome variables between the two groups before and after

intervention. Paired t-tests were used to examine within-group differences at baseline,

3 months, 6 months, and 12 months post-intervention. A linear mixed-effect model

that adjusted for the demographic data and baseline outcome variables was used to

examine the changing amount of outcome variables from baseline to 3 months, to 6

months, and to 12 months post-intervention between the intervention and control arms.

Participants were considered as a random effect. First-order autoregressive was used

in the mixed-effect model analysis with the restricted maximum likelihood (REML)

approach. A p-value < .05 was considered statistically significant.

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Table 1. Outcome measures and collection time points

Measures Baseline 3rdmonth 6th month 12th month

Demographic data & disease

characteristics

Body mass index -

HbA1c

Lipids (TC, HDL-C, LDL-C,

TG)

Renal function: UACR, GFR

Stage of change for insulin

injection

Insulin injection adherence -

Appraisal of insulin injection

Empowerment -

Self-efficacy -

Diabetes distress -

Quality of life -

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Table 2. Individual intervention plan

Stage of Change Strategy Process of Change

Precontemplation Use examples in which good/bad

glycemic control has a

positive/negative impact on

significant others to help patients

reflect on their own HbA1c control

Explain current health condition to

patients through the changes in the

curves of the their data

Use UKPDS Risk Engine to predict

the risk of cardiovascular disease

and cerebrovascular event in the

future 10 to 20 years in individual

patients

Consciousness

raising

Build a well-established trusting

relationship

Use empathic skills to recognize

the feelings of patients (fear, worry,

guilt, etc.)

Guide patients to explore the

influence of glycemic control and

physical health on their lives

Explain that accepting insulin

injection does not mean failure of

treatment or advancement of

disease but the natural progression

of diabetes

Assess the decisional balance for

insulin injection and provide

clarification

Guide patients to think about

possible benefits brought about by

insulin injection to themselves and

their family

Dramatic relief

Contemplation Invite patients to compare the

perceived pros and cons

Self-reevaluation

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List all medications for treating

diabetes and their mechanisms,

maximum dose, expected range of

improvement in HbA1c, possible

side effects, and costs

Enhance the positive effects of

insulin injection

Guide patients to consider the

importance of good glycemic

control

Dramatic relief

Preparation Assess the decisional balance for

insulin injection and provide

guidance

Dramatic relief

Set short-term targets for glycemic

control and insulin injection with

patients

Self-reevaluation

Assess family support and provide

patient education

Provide resources that give instant

feedback and build a platform for

instant interaction

Helping relationship

Systematic

desensitization—Gradual

self-administered insulin injection.

Patients first receive insulin

injection given by healthcare

professionals at medical

institutions, and then slowly

perform injection by themselves

from withdrawing insulin, pushing

away air bubbles, and injecting.

Give rewards for each progress

made

Instruct patients in the techniques

for insulin injection and medicine

preservation

Use the results of blood-glucose

self-monitoring to guide patients to

Counterconditioning

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think about the relationship

between insulin injection, diet, and

physical activity

Provide patient education on

blood-glucose self-monitoring and

assessment on the ability to deal

with hypoglycemia

Ask patients to continuously keep a

daily record of the dose, time, site

of injection, administration of

blood-glucose self-monitoring, and

incidents of hypo/hyperglycemia in

the “Health Guardian Pamphlet”

Action Educate family members to

provide support for patients

Build an instant online interactive

system with professionals to

provide feedback to patients

Helping relationship

Encourage patients to adhere to the

insulin injection plan

Healthcare professionals conduct

telephone interviews and schedule

return visits for patients on a

regular basis

Instruct patients how to adjust their

diet and exercise flexibly according

to insulin injection so as to

decrease the chance of termination

caused by barriers

Teach patients to adjust the dose of

insulin according to the results of

blood-glucose self-monitoring

Reinforcement

management

Patients promise to set mid-term

and long-term goals

Self-liberation

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Table 3. Motivational group activity

Stage of Change Strategy Process of Change

Precontemplation Listen to fellow patients in the

stages of action and maintenance

share the benefits of insulin

injection and the ways to overcome

obstacles

Try out insulin injection

Use pictorial or multimedia

materials to illustrate the

relationship between insulin and

blood-glucose

Self-reevaluation

Preparation Listen to fellow patients in the

stages of action and maintenance

share the benefits of insulin

injection and the ways to overcome

obstacles

Try out insulin injection

Use pictorial or multimedia

materials to illustrate the

relationship between insulin and

blood-glucose

Self-reevaluation

Action Share experience in insulin

injection and provide support and

solution

Build mutually supportive

partnerships with fellow patients

Reinforcement

management

Maintenance Share successful experience with

other patients to enhance the

motivation of the patient to

continue insulin injection

Reinforcement

management

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Table 4. Insulin injection follow-up management

Stage of Change Strategy Process of Change

Preparation Follow up problems with insulin

injection, e.g. dose, site of

injection, and technique

Reinforcement

management

Action Guide patients to examine the

relationship between insulin

injection and changes in

blood-glucose to strengthen their

self-efficacy

Self-reevaluation

Ask patients to continuously keep

a daily record of the dose, time,

site of injection, administration of

blood-glucose self-monitoring, and

incidents of hypo/hyperglycemia

in the “Health Guardian Pamphlet”

Counterconditioning

Maintenance Encourage patients regularly when

HbA1c level decreases

Provide care and support

Reinforcement

management

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Refuse

Figure 1. Intervention flowchart of the intervention arm

Individual intervention

Motivational group

activity (as participants)

Recruited participants

Baseline assessment

Action

stage

Management without

special intervention

Accept

HbA1c≧8.5%

HbA1c < 8.5%

* Motivational group activities are held once every two months. Patients in the stages of action and

maintenance will be invited to share their experiences during the activity.

Measurement at

6 months

post-intervention

Measurement at

3, 6, 12 months

post-intervention

Measurement at

3 months post-intervention

Measurement at

12 months

post-intervention

Individual intervention

Insulin injection

follow-up management

Motivational group

activity

Precontemplation &

Contemplation stages

Preparation stage

Maintenance

stage

HbA1c≧8.5%

HbA1c≧8.5%

HbA1c<8.5%

HbA1c≧8.5% HbA1c<8.5%

HbA1c < 8%